What Is the Evidence?

Abstract

Abstracts identified through the keyword search were reviewed and evaluated for their relevance to the clinical question. A total of 27 abstracts were identi-fied; however, abstracts containing information not concerned with the clinical aspects of treatment or in-volving another species (ie, rat) were excluded. Once relevant abstracts were identified, the articles were reviewed to evaluate the quality of evidence provided by each through use of a published grading system for studies in veterinary clinical nutrition, 1 with I repre-senting the highest grade (ie, a properly designed ran-domized, controlled clinical trial involving the target species) and IV representing the lowest (ie, opinion based on clinical experience). Factors such as study de -sign, results obtained, and relevance to the canine spe-cies were also evaluated.Two studies 2,3 were identified in which the use of tylosin for treatment of chronic diarrhea in dogs was evaluated. The first study 2 was a prospective case se-ries involving 7 colony Beagles with chronic diarrhea. Those with persistent diarrhea (of at least 1 month’s duration) and fecal consistency scores of 3.5 to 4.5 (median, 4.0), based on a 5-point scale with 1 being hard, dry, and crumbly feces and 5 being very watery diarrhea, were treated with tylosin and had firmer feces 2 to 3 days afterward, with a median consistency score of 2.75, which was significantly (